An illustrative calibration member made from a material that scatters light may be used to perform a calibration operation with respect to an optical measurement device having a plurality of light sources and a plurality of detectors distributed among a plurality of modules. The calibration member may form an exterior surface configured to support the optical measurement device and scatter photons of light emitted by the optical measurement device. The calibration operation may be performed based on arrival times of the scattered photons detected by the optical measurement device.

A light sensing method having a sensing order adjusting mechanism is provided. The method includes steps of: in a previous sensing cycle, sensing a first light signal that is emitted by both of an ambient light source and a light-emitting component and then is reflected by a tested object; in the previous sensing cycle, sensing a second light signal that is emitted by both of the ambient light source and the light-emitting component and then is reflected by the tested object; in the previous sensing cycle, sensing an ambient light signal emitted by only the ambient light source; and in a next sensing cycle, sensing the first light signal, the second light signal and the ambient light signal in an order different from that in the previous sensing cycle.

A method of distinguishing effective pulses from test pulses in a scintillation detector that generates measurement light pulses includes providing a regularly-pulsed test light source that produces individual test light pulses having a time-dependent course of relative light intensity, which differs from a time-dependent course of relative light intensity of the measurement light pulses. The test light pulses are provided to a light detector for measurement of the test light pulses. The time-dependent courses of the relative light intensities of the test light pulses are analyzed. The measured pulses are separated into the test light pulses and the measurement light pulses according to the different time-dependent courses of the relative light intensities. The detector includes a scintillator, a light detector, a regularly-pulsed test light source that is adapted provide test light pulses to the light detector for measurement, and an electronic measuring circuit.

An illustrative calibration member made from a material that scatters light may be used to perform a calibration operation with respect to an optical measurement device having a plurality of light sources and a plurality of detectors distributed among a plurality of modules. The calibration member may form an exterior surface configured to support the optical measurement device and scatter photons of light emitted by the optical measurement device. The calibration operation may be performed based on arrival times of the scattered photons detected by the optical measurement device.

A light sensing method having a sensing order adjusting mechanism is provided. The method includes steps of: in a previous sensing cycle, sensing a first light signal that is emitted by both of an ambient light source and a light-emitting component and then is reflected by a tested object; in the previous sensing cycle, sensing a second light signal that is emitted by both of the ambient light source and the light-emitting component and then is reflected by the tested object; in the previous sensing cycle, sensing an ambient light signal emitted by only the ambient light source; and in a next sensing cycle, sensing the first light signal, the second light signal and the ambient light signal in an order different from that in the previous sensing cycle.